Internal-combustion engine charge forming apparatus



R. M. ANDERSON Jul 31, 1945.

INTERNAL-COMBUSTION ENGINE CIiARGE-FORMING APPARATU Filed N o'v. 25,1942 "s SheetS Sheet 2 f July "31, 1-945; 3. M. ANDERSON I 2,380, 4

INTERNAL-COMBUSTION ENGINE CHARGE FORMING APPAhATUS Filed Nov.25, 1942 sSheets-Sheet s Z2 @M a INVENTOR AA YMO/VD M. ANDERSON ORNEY PatentedJuly 31, 1945 IN TERNAL-COMBUSTION ENGINE CHARGE FORMING APPARATUS'Raymond M. Anderson, Detroit, Michl, assignor to Evans ProductsCompany, Detroit, Mich., a a

- corporation of Delaware Application November 25, 1942, Serial No.466,835

ENT OFFICE 22 Claims, This invention is a continuation-in-part of myrade or heavier fuels or in cold weather, or else,

co-pending application,jSerial No. 279,394, filed June 16, 1939, forInternal combustion engine charge forming apparatus and relates to suchapparatus-and more particularly to certain improve-- ments in automaticheat controls for a fuel mixture heater or in exhaust gas flowregulating valve units and their controls for heating the inductionmanifolding system of internal combustion engines, not. only as they maybe used with the par ticular charge forming apparatus, of my aboveidentified parent application, but; to such-im proved heat controls orvalve units per se, or as they may be used in various other arrangementsor with other types of internal combustion engines. v

The disclosure of the first embodiment'oi this invention in .thespecification and drawings herein is'identical with and embodies thedisclosure of the exhaust gas fiow regulatingvalve unit in myaboveidentified parent application, which has claims to various other chargeforming features and combinations and has certain claims to com.binations which include this exhaust gas flow regulating valve unit asan element thereof, but rather. broadly set forth and, along with otherlimitations and elements'relative to the special or specificcharge'forming apparatus ofthat ins vention, such as the long mixtureheating passage to carry a small part of the total air supply or theseparate supplies of auxiliary volatile fuel;

7 whereas, as noted above, the invention of-w-sthis application,including its first embodiment which may be considered as a division ofthe saidparent application, relates to the more specific aspects andfeatures of my improved automatic heat controls or exhaust fiow,regulating valve units, either per se or in combination with ordinary orany types of internal combustion engines and their manifolding, andwithout regard to the rest of the special charge forming apparatusofsaid parent application.- 1

In general, the objects oi this invention are to provide improved,simplified, and more accurate or flexible thermostatic or automatic heatcontrols or valve control units for the heating oi the induction intakemaniioiding systems of internal combustion engines or a heated partthereof by a regulated flow of exhaust gases. V n

More specific objects are to provide such heat control units which areparticularly well adapted to give sufiicient fuel vaporizing heatmetered as needed and a substantially constant limiting temperature,satisfactory operation, and economy in internal combustion enginesoperating on low to provide designs adapted for ordinary enginesoperating with ordinary-gasoline and under usual conditions to give ahigher economy due to more heat except at heavy load or full throttleconditions, to reduce or eliminate valve pounding, to

I give a safety valve or blow-oil! valveseilect by the exhaust gaspressure acting to open the valve a ainst a biasingforce preferably by aweight tending toholdthe valve closed, to provide a resilient thermostattending to open the valve for less heat, this thermostatpreferably beinga bimetallic coil carried by and moving with the valve to act in onlyonedirection through an initial .lost motion'connection so that it does notact on the valve at its lower temperatures, to provide an the valve andthis resilient stop being formed by the thermostat itself, and toprovide, in combination with a valve held closed by a weight or thelike. a separate spring or yielding stop to define the valve closedposition and to operate at all times. I

-In the drawings, in which like numerals are .used to designate likeparts in the several views throughout: i l 'Fig. 1 is a general viewshowing in elevation an embodiment of the charge forming and regulatingapparatus of the above identified parent applica- Fig. 2 is a detail endelevation view of this exhaust gas regulating unit as viewed from theleft in .Fig. 1;

Fig, 3 is a fragmentary and elevation of the other side of this exhaustgas regulating unit with portions being broken away;

Fig. 4 is a vertical sectional view of the valve unit taken on the line4-4 of Fig. 3;

Fig. 5 is a sectional view taken on the line 5-! of Fig. 6 but withports of the exhaust manifold shown in plan and not sectioned, thisfigure showing a second embodiment of this invention and its applicationin conventional manifolding;

Fig. 6 is a front elevational view of the organization of Fig. 5, butwith portions being broken away and shown in section, this figureshowing the application of the second embodiment of my improved valvecontrol to a well known type of mixture heater and valve or hot spot inthe intake manifold and the associated exhaust manifold and connections;

Fig. 7 is a section taken on the line 'I-I of Fig. 6;

Fig. 8 is a part end and part sectional view taken on the line 8-8 ofFig. 6;

Fig. 9 is a part end and part sectional view taken on a line like Fig.8, but showing a third embodiment or other or additional features whichmay be employed and a slight change in v the bimetallic coil; and

Figure 10 is a front elevational view or a view looking from the left inFig. 9.

While in general the exhaust heat control valve units or the like withinthe purview of this invention may be applied to or used in combinationwith various sorts of internal combustion engine intake manifoldingsystem heaters, yet, since the specific design of the first embodimenthereof is particularly well adapted for satisfac-w tory operation with aparticular manifolding system to vaporize heavy or low grade fuels in asmall part of the total air supply at higher limited temperatures, Ihave included herein those portions of the drawings and specification ofmy above identified parent application which relate more directly to thepresent invention and I have briefly summarized herein the rest of theorganization of such parent application; however, I intend to includeherein by reference the balance of the disclosure of this parentapplication in order to give, if desired, a completa'understanding ofthis particular embodiment or application of the present invention.

However, as noted above, it is to be understood that this invention, andparticularly the broader aspects of the first or divisional embodimenthereof is not intended to .be limited or necessarily restricted to usewith this particular sort of internal' combustion engine charge formingarrangement, sinceit will be generally apparent to those skilled in thisart and will be seen by analogy with my second embodiment that therelative proportions, biasing forces, temperature ranges, and the like,can be changed to use this general design in engine mixture heatershaving quite different requirements, such as conventional engines usingordinary gasoline.

As shown in the general organization 'view of Fig. 1 the charge formingand regulating apparatus of the said parent application is applied to aconventional type of automobile or truck gasoline engine 2 having theusual exhaust manifold I, exhaust pipe 98, the usual intake manifold 3drawing in air and fuel from an intake conduit and carburetor of thedown-draft type having the conventional air cleaner II 2 and having theusual throttle and choke therein. Carburetor unit I is here a specialmulti-fuel type,

as generally described herein.

In Fig. 1,- unit I28 is a special economizer to supply metered heatedair from the schematically shown pipe I34 into the intake beyond thethrottle under the control of the movable throttle plate through theconduit I33.

Number H is an anti-detonation unit to meter exhaust gas into the intakemanifold only under heavy load conditions.

It is to be understood that these two units are not material to thepresent invention.

Closely adjacent the multi-fuel carburetor I is mounted a compact, fiatvaporizervheater unit 5, which is externally jacketed to provide anexhaust gas space entirely surrounding the inner coiled or fiat spiralmixture heating passage. The exhaust gases flow to and from this heater5 by connections 6 and I respectively, which pipes may also support theheater. Thus, the desired heating fiow of exhaust gases is controllablybypassed from and back to the exhaust manifold I and exhaust pipe 98 bythe valve unit I03, etc., which forms the first embodiment of thisinvention. This valve unit is controlled by the exhaust gas temperatureand how rate. Inside of the heater 5 is a fiat, spiral air and fuelmixture heating and vaporizing passage, the inner end of which issupplied by a passage including pipe I with a small part (5% to 10%) ofthe engine's total air supply from the intake conduit between the chokeand air cleaner and with a main varying-metered fuel supply of oil orgasoline as selected by suitable snap action valves in the carburetorunit I, andas mixed or atomized by the mixture atomized by a primaryventui-i at the entrance to pipe 8 and forming a part of the combinedcarburetor unit I.

Thus, in thisspeciflc embodiment of the parent application, the majorpart of the engine's air supply is sucked down through the intakeconduit (comprising the riser, the mixing chamber, and the intakemanifold) in the usual fashion, while asmall proportion (preferablyabout 5% and less than 10% of the total air supply) is drawn through aseparate passage, which includes horizontal connections 8 and 8 and thesubstantially horizontal, tortuous, mixture-heating passage in theheater 5. This passage is supplied by the above noted primary venturifrom one of the two heavy and light fuel bowls in the carburetor I asselected by snap action valves. This superrich mixture is heated to ahigh temperature so that the sprayed fuel is partly gasified, partlyvaporized, and the balance finely divided. For the sake of simplicity.this condition is hereinafter referred to as vaporized.

It will be seen that, for starting and until the engine has come up totemperature, only gasoline or the like will be supplied to thevaporizer-heater units venturi for discharge into the annular space inthe composite inner venturi of the multi-venturi set of the main mixingchamber (none of which are shown here). Manually operated orautomatically controlled valves may control the change-over fromgasoline to heavyfuel, or vice versa, at starting or at other times, asis well known in this art.

Another feature of the parent application is the provision of auxiliaryfuel supplying means to supply volatile unheated fuel directly into theintake conduit concurrently with the varying conventional type ofcompensatingjet' assembly andidling assembly and also embodies a con-=ventional accelerator pump, alloperating only on gasoline tocontinuously supply auxiliary volatile fuel, together with themainvaporized light or heavy fuel supply through the heater which also goesinto the same main mixing chamber venturi.

the super-rich heated mixture be maintained within reasonably closelimitations. In the present embodiment it has been found that, althoughbetter results are obtained the more closely'the mixture temperature isregulated,satisfactory results are obtainable with variations up to50degrees F. In the present'embo'diment a closere ulation is accomplishedby regulating the flow'of exhaust gas through the by-pass circuit whichincludes the vaporizer-heater.

Referring to Figs. 2, 3 and 4, it is seen that the unbalanced exhaustregulating valve 99,

which is preferably pivoted atone edge by being fixed on rockable pinIOI' journaled inthe side walls of the Y fitting I00, may seat against ashoulder I02 to close thisleg of the 'Y fitting to force all of theexhaust gas around through the vaporizer-heater. When wide open,valve'llll seats against shoulder HI. To prevent fluttering and poundingon its seat, this valve is inertia damped by a comparatively heavy flywheel l04 fixed on its pin IIJI. This wheel carries a which is'designed'to'provide a relatively high but limited,1o'r constant, when possible,temperature for the heater. However, it will be seen that this designcould be readily modified to provide a t is quite important that thetemperature of V lower and variable temperature, as for use with anordinary gasoline'automobile engine hot spot.

Also, in this first form my heavy inertia disc or wheel I04 willpractically eliminate valve pounding, and its offset weight I03 willtend to hold the valve closed for maximum heating, even when thebimetallic strip I01 is cold and does not exert any appreciable valveopening eifect, so that this weight I03 adjacent its periphery tobias'the valve toward its closed position against :seatorshoulder IE2.

It will be noted that a'bolt I03 secures this weight to the wheel in anyone of the plurality of holes I05 so that the weight is adjustableangularly around the periphery of the wheel; and since the bolt hole inthe weight itself is eccentric, the weight may be moved in or outradially, both of which movements permit a nice adjustment of theeffective lever arm of the Weight acting'on the valve so that thetemperaweight gives a safety or blow-off valve efiect, permittingasudden increase in exhaust gaspressure or flow to open the valve to acontrolled amount and thus prevent undue heating, and to have a heatinggas flow regulating action to give a more constant'heating ortemperature inthe heater 5.

This weight also acts with a progressively decreasing torque, dueto itsdecreasing effective lever arm,as-it,opens so that it isstrongly heldclosed'at lowexhaust flow rates and more easily held open when it isopenat high exhaust flow rates to correct'for the decreasing effective areaofthe valve 99. I I

-I 'prefera weight, such'as I63, to a spring to bias my valve since aweight aids by the inertia *or damping" effect and issimpler and notadversely affected bythe high temperature. The

several holes I05 permit the effective lever arm of the weight and alsoits change in lever arm as it moves to be varied while the rotationaladjustment of eccentric weight I03 gives a" second and finer adjustmentfor calibration or the like. If desired, and as shown'in the secondembodiment,

portion- I09 can merely loosely engage pin III] o that the thermostat isonly a one-Way action to open the valve, and the various features ofthis ture setting may be varied for different installa- I tions, fordifferent fuels, for winter and summer 5 set at low temperatures and attemperatures slightly above the desired setting, which, as noted 2above, may be about400 degrees FL,v to move the valve toward seat III toanextent dependent on the temperature and the pressure exerted on thevalve. It will be apparent that since this bimetallic element is mountedadjacent the fitting Iilll its action will be responsive'to exhaust gastemperatures. The butterflytyp'evalve 99 itself is I responsive to therate of flow of the exhaustgas,

which is a functionof' engine load-speed conditions; 4

- It will be apparent that in normal operation this exhaust gasregulator valve will occupy someintermediate position dependent upon theexhaust gas temperature and flow-rate to limit and to regulate theexhaust gas made availableto the In the first embodiment just describedI :have

*provided a heatcontrolling exhaustvalve unit second embodiment maybeemployed here or the features of this first embodiment, such as the useof the inertia wheel I04 and the adjustable weight IE3 may be used inthe design of the second embodiment.

I Referring to the second embodiment of my invention, Figs, 5, 6, '7 and8 in particular, illustrate the central parts of an intake manifold andan, exhaust manifold, togetherwith the combined mixture heater or hotspot, and its exhaust gas flow regulating valve. Before proceeding tothe more detailed description of these parts, it should be notedthat thestructure of the exhaust and intake manifolding, the hot spot or heater,and

the valve itself, are of a conventional and well known form, in fact,these figures illustrate the structure employed in the present Chevroletautomobile or truck engine and show how that conventional' structure maybe easily modified to embody my inventionin the controls for the exhaustnow regulating valve. Thus, the particular structure of' themanifolding, the heater, and the 'valve proper, form 110 part of thisinvention per se, andenter into this invention as environmentor'background therefor, or in combination with [vaporizer-heater andconsequently the mixture temperature.

my improved features.

As shown, the intake manifold 3 (the ports not being shown), has thecentral, integrally cast hot spot or heater portion 305 which, as isunderstood, is to beused with a down-draft carburetor throttle barrel orintake riser mounted on its upper portion, so that the intake riserpipe, or throttle barrel 39 as shown in Fig. 9, maybe matched'to openingI4 and suitably secured, as by bolts j-through the bolt hole Ida. Thus,the air and carburetted fuel will fiow down'and i'nthedirections'indicated' by the double headed-arrows through the'exhaustjacketed and heated chamber 13 which is in th form of a tube having aclosed bottom l5 and arranged so that, adjacent its bottom, the air-fuelmixture splits three ways, one part going rearwardly through the openingI2-and the connecting rearwardly extendingpassage l I having the openingill adapted to be connected with the common opening to the two centerSiamesed intake ports, and the other two parts going left and right intothe left and right two openings I6 and into the two end portions of theintake manifold 3 to go on to the two remaining pair of ports (notshown) of the six cylinder engine.

The conventional exhaust manifold 4 has the usualports, two of which areindicated at M,

and its central portion is shaped to direct the exopening 2t! into theusual exhaust pipe, while,

when the valve is practically closed, as shown at 399 in Fig. '7, almostall of the exhaust gas flow will be diverted or icy-passed upwardlythrough the passage portion I! around the conduit or passage II and intothe annular passage 19 past the valve and so to the exhaust pipe. Notethat the paths of the exhaust gases are shown by the single headedarrows.

The bottom [5 of the heating tube 13 is provided with a cast-in portion2| to form a stop for the upper end of the unbalanced valve 399 to thusdefine its closed or heating position, in which there will be a slightleakage flow since the other end of the exhaust valve does not quiteseat on the adjacent wall portion 302 which would otherwise be theclosed position valve seat. When the valve is entirely open it seatsagainst the wall portion or seat 3H.

It will be appreciated that the unbalanced valve 39'9wi1l be biasedtoward its open or non-heating inertia weight with the offset portion303 and the reduced end portion 384 having a hole therein to receive theshaft and be secured thereon as by the cotter pin SMa'or the like whichextends through a corresponding hole in shaft L The other outside end ofshaft 3i]! is slotted, as at 308, to

receive the suitably secured inner end of the coiled bimetallic strip30! having its other orfree end acting against a relatively fixedabutment.

As noted above, the foregoing detailed structure is identical with theChevrolet hot spot, manifolding, and valve unit, except for theparticular arrangement and action of the weight 303, the thermostat 301,and the adjustable thermostat abutment 3H], and this portion of thedisclosure will indicate how easily this well known control unit may bemodified to embody my invention and thus have a different and improvedoperation.

I have modified this conventional heat control unit so that the valve isalways biased toward closing position, as in my first embodiment,preferably a weight acting on a decreasing effective lever arm as thevalve is'openedi If desired, this weight may be made adjustable as in myfirst form. Also the yielding or resilient thermostat actsto' open thevalve for less heat preferably through a one-way connection, and aninitial lost motion with suitable adjustments.

Thus, instead of the offset weight portion 303 extending up and a littleto the rear so that it would bias the valve toward open position with aprogressively increasing biasing effect as the valve is opened, as'isdone in the Chevrolet arrangement, my offset weight portion 303 imounted in an angular position so that when the valve is closed it issubstantially-in the position 383 as shown in Fig. 7 so that it tends toalways bias the valve toward closed or heating position with aprogressively decreasing biasing effect as the valve is opened or sotheweight is moved toward the position as shown at 303 in Fig. '7.

Referring tolthe arrangement of the thermostat which is carried by, andalways movable with, the valve member or its valve shaft 39!, mybimetallic coiled strip does not resist opening movements of the valveor tend to close the valve, as in the above noted Chevrolet constructionbut acts in the opposite direction; the coiled bimetallic strip 301being arranged and wound in such a direction that its free and slightlyhooked end portion 309 tends to move counter-clockwise, as

the initial lost motion if this should be desirable in any particulardesign.

Thus, the position of the abutment pin 318 may be manually adjusted bysuitable means, as my mounting it in one of the several holes Mild tothus manually adjust or pro-set the rangeof the thermostat or thepointat which it will push off from pin 3H] and. thus start biasing thevalve. This manual adjustment will be useful for calibration or forsetting the unit for different fuels or for different climaticconditions such as cold or hot weather.

It will be seen that my resilient thermostat can act on the valve inonly one direction and thus has a one-way action, preferably through aninitial lost motion connections Also the thermostat, which acts in thesame direction as the exhaust gas pressure or flow, may not always beoperating since an increased exhaust gas pressure will hold the valveopen to a degree where 309 does not engage pin 3H1.

It will be noted that when the thermostat is hot, as it will be duringnormal operations, it

will limit closing motions of the valve and thus serve as a resilient orcushioning stop, preventing the pounding of the valve on its seat oragainst its end stop I2l due to the fiutter induced by pulsations intheexhaust gas flow acting to intermittently bias the valve open.

However, in cases where the weight of the valve itself and the partsmoving therewith including the thermostat and the weight 303 do notprovide enough inertia. dampeningt 1i 1 nate this objectionable poundingsufficiently, I

may provide a resilient or spring cushioning stop to limit or define thevalve closed or heating position'and to actatall-times, even when thether-' m-mat isrfiot a e on the-valve, aSP h'eI it istoo cold. V

" Thus, I have provided the leaf spring; bent or curved as shown andhaving its upper end secured on theinner flat side of the offset weightportion 303 by the two screws 'or'the like, 3|and 32. The lower or freeend portion of thespring corresponding tapped and threaded'hole 26 'inthe boss cast on' 'the exhaust manifold .4 as

301a, thus saving an extra pivot and permitting shown. The stoporabutment forming rod 21 may be locked in any desired adjusted positionby the lock nut 28 engaging the same threaded portion. It will'be seenthat thepoint at which the'spring 30 engages or starts to act may beadjusted by bending the spring in or out, as is well known in connectionwith leaf: springs, by having screw 32'formedwith ;a portionsuch as alock nut thereonlto engage on'the inner sideof. the spring 30 so that asscrew 32 is screwed in or out it will adjust'the free end of spring or,as

shown, by screwing the stop'rod 21 in or out a'more compact and'neaterassembly'.

Link 51 may be made sufllciently thick and heavy so that it isvbiased'by its own. weight and thus held: to preventvibration andclicking or. pounding. Ifdesired, spring 52 may be mounted on the rod 46between the suitably fixed collar or abutment63 thereon and the swivelblock 52 on the link 51 so that this weak spring yieldingly holds: link51 against its stop 3l0 except when the throttle is opened. I

It will be seen that I have provided here a lost motion connection, sothat when the throttle 40 is substantially fully opened as underfull'load conditions the rod wil1 be listed until it takes up the lostmotion and the nut 49 engages the swivel block onthe link 5'! to liftthe link or swing it clockwise and to thus similarly move the pin 58.This will change the range or startingpoint of the thermostat 301a or,considered in another way, rod '46 will push the valve 399 open throughthe-resilient thermostat 301a when the throttle is'opened wide. Theamount 'of this lost -motion canbe adjusted by moving nut 49 along"modify and add to the structure ofFigs; 5 to 8,

so thatthe manual adjustment of the position of the abutment engaged bythe free end of=the bimetallic spring (here designated as 301a) is doneby the throttle}. v

In Figs/'9 and 10 the structureis identical w'ith Y Figs. 5 tot exceptas noted. The bimetallic spring 301a is shaped or bent slightlydifferently,

so that its free end 309a is slightly further around mounted on thethrottle shaft 4 ljthe exposedend of which has suitably fixed thereto aswingable link 48, having in its free enda hole 43 toreceive and journaltherein the bent-over, upper end portion 44 of the link rod 46 suitablyheld'in this hole, as by the cotter pin 45. J It will'b'e seen that rod46 may be bent or otherwise shaped toclear act directly on=the valve orvalve member through some other projection from the valve shaft such Iasthe valve weight 303. Y'

Thus, in Figs. '9 and 10 I;have disclosed an arrangement whereby therange or action of the thermostat isadjusted or: changed in accordance35,

with'engineload conditions preferably by throttle movement and also.preferably, but not' necessarily, through a lost motion connection sothat there is normal or full heating up to substantially wide openthrottle although this point can beadv,justed as desired.

i within the scope'of this invention will-becomeapof the valve shaftwiththe thermostat,the therthe interfering heater portion; 3,0 5. Thelower end portion of rod 36 is threaded, as at 48, and carries thereonthe adjustable abutment forming nut 49 held bya lock nut 50; Asshown,this lower portionof'the rod abovethe out His freely slidable in andthrough the-opening 53 through theswivel block 52; whose reduced pinforming end portion 55 is pivotably mounted or swivelled The downward orcounter-clockwiseposition or motion of link 51 is limited by pin 3m,whose position maybe adjusted as bythe holes 3l0a. The other, or fixedpivotend of link 51, has a parent'to those skilled in this art from theforegoingteachings.- Forexample, i'neither embodiment'there may be othersorts ofthermostats, or cushion stops, a balanced'valve may be used toeliminate the exhaust gas pressure biasing eflfect, within'the broaderscope a spring or other biasing means maybe used in lieu of the weight.The weight or-the like may be on the same end mostat may be shielded orotherwise controlled to regulatethe cooling air flow thereover-or the'in a suitable hole formed'in the free end portion bearing forming hole59 to receive and pivot it on the shaft Milt-inside of the bimetallicstrip transfer of ,heat'thereto, and, of course, the several parts maybeof various proportions and designs. J I t Although the foregoingdescription of the three illustrated, embodiments is necessarilydetailed, yet it is to be understood that this detailed description Jand the specified terminology is not intended to be restrictive and'thatvarious omissions, rearrangements or othermodificationsof partsin'addition to those mentioned herein, may be employed without departingfrom the scope or spirit of the inventionas'claimed'herein. I 1

Iclaimzw- 1 1. A heat-control for the manifolding system of internalcombustionengines, including means biased toward open positionby thepressure of exhaust gases thereon, exhaust gas temperature responsivemeans biasing said valve toward open Iposition, and an inertia weightcarried by said and acting to bias said valvetoward'closed position.

2. An exhaust gas valve unit to control the flow of exhaust gasesthrough an internal combustion engine air-fuel mixture heater comprisingan unbalanced valve biased toward its non-mixture heating positions bythe pressure of the exhaust gases thereon, means to bias said valvetoward its mixture heatingposition, and a thermostat heated by theexhaust gases to bias said valve toward its non-heating positions.

3. A heat control for the induction manifolding systems of internalcombustion engines including a heater and connections for supplyingexhaust gases from the exhaust manifold to said heater, comprising avalve to divert the flow of exhaust gases through said heater whenclosed, automatic control means tobias said valve toward open positionin accordance with operating conditions of the engine, and a weight tobias said valve towards its'closed position.

4.. The organization as set forth in claim 3, 'in which said weight ismountedto have progressively decreasing effect as the valve is opened.

5. A heat control for an internal combustion engine mixture heater,including an unbalanced valve for diverting exhaust gases from theexhaust manifold through the mixture heater; said valve being adapted tobe opened to by-pass the exhaust gases away from themixture heater bythe pressure of the gases thereon, a thermostat also-biasing said valvetoward open position when hot, and a weight biasing said valve towardclosed position.

6. An exhaust gas valve unit to control the flow of exhaust gasesthrough an internal combustion engine mixture heater, comprising avalve, means to bias said valve toward mixture heating position, and athermostat having a lost motion connection with said valve to start tobias it toward non-mixture heating position only after a predeterminedtemperature rise.

7. An exhaust control for an internal combustion engine inductionmanifolding system heater, comprising a swingably pivoted valve todivert exhaust gases through said heater when closed, a heavy inertiadisc fixed to rotate concentrically with said valve to damp out flutteror pounding by its inertia, and means to automatically control saidvalve in accordance with engine operating conditions, including athermostat and a valve biasing weight mounted in an eccentric positionon said disc.

8. The organization as set forth in claim 7 in which said weight isitself an eccentric, adjustably mounted so that the effective lever armand position of the weight can be adjusted.

9. A heat control for the air-:fuel mixture heater of an internalcombustion engine having a movable throttle, said control comprising avalve unit for controlling the diversion of exhaust gases through themixture heater and including a valve, biasing means including athermostat biasing said valve toward its non-heating position, andthrottle operated means for applying a force to said valve as saidthrottle is opened to assist said thermostat in moving the valve towardits non-heating position.

10. A valve and automatic control unit for an air-fuel mixture heater ofan internal combustion engine having a movable throttle, said unitcomprising a valve for controlling the flow of exhaust gases throughthe'heater, biasing means.

including a resilient thermostat for controlling said valve, and meansfor modifying the action of said thermostat in accordance with throttleposition, including a one way connection acting between said throttleand said resilient thermostat.

11. A valve and automatic control unit for an air-fuel mixture heater ofan internal combustion engine having a manually movable throttle, saidunit comprising a valve for regulating the diversion of exhaust gasesthrough the heater, biasing means for controlling the position of saidvalve and including a coiled bimetallic strip having one end acting onsaid valve, and means including aone way connection to positively movethe other end of said bi-metallic strip only when the throttleis movedin one direction.

12. A heater for the air-fuel mixture induction system of an internalcombustion engine, said heater including a valve to regulate the flow ofexhaust gas through said heater, and an automatic control therefor, saidcontrol comprising biasing means for controlling the actuation of saidvalve and including a coiled .bi-metallic strip thermostat having oneend acting on said valve and biasing said valve only towards itsnon-heating position, and means, including a one way, lost motion, tomanually adjust the position of the other end of said strip to thusmodify the action of said thermostat in accordance with operatingconditions. v

13. A heater for the air-fuel mixture in the induction system of aninternal combustion engine, said heater including a valve to control theflow of exhaust gases through said heaterv and an automatic controltherefor, including a resilient thermostat acting between said valve anda relatively fixed support through a.lost motion connection to bias saidvalve toward its non-heating position only after said thermostat hasreached an intermediate higher temperaturaand means to manually adjustthe positioin of said support to thus modify the action of saidthermostat.

14. An automatically controlled heat regulating valve unit for anair-fuel mixture heater .in the induction system of an internalcombustion engine, said unit comprising an unbalanced valve toward itsheating position, and a yielding or cushion stop determining the extremeheating positions of said valve to prevent its pounding.

15. An automatically controlled heat regulating valve unit foranair-fuel mixture heater in the induction system of an internalcombustion engine, said unit comprising an unbalanced valve biasedtoward its non-heating position by the flow of exhaust gases andcontrolling said flow, biasing means toautomatioally control theposition of said valve including a thermostat and means tending to holdsaid valve in its extreme heating position, and a yieldable cushion stopto prevent valve pounding, comprising a relatively fixed abutment and aspring fixed with respect to and always movable with said valve toyieldingly engage said abutment only as the valve moves to its extremeheating positions.

16. The organization as setforth in claim 15, including means tomanually adjust the normal relative positions of said spring andabutment gas pressure thereon, means to bias said valve toward closedposition and a resilient thermostat heated by the exhaust gases and,when hot, biasing the valve toward its open position and yieldinglyresisting closing movements of the valve whereby the thermostat alsoserves as aresilient stop to limit the closing movements of the valveand prevent pounding during normal operation.

,18. An exhaust gas heater for the induction system of an internalcombustion engine,inc1uding a valve to controllably divert the flow ofexhaust gases through said heater when closed and biased towards itsopen, positions by the exhaust gas pressure thereon, control meansto-variably bias said valve and including a'thermostat having a lostmotion and one-way operating connection between said valve and arelatively fixed member, so that said thermostat acts upon the valve inonly one direction and not at the cold or lower end of its temperaturerange.

19. An automatically regulated exhaust gas heater unit for the inductionsystem of an internal combustion engine, including a swingably pivotedvalve to divert exhaust gases through said heater when closed, and meansto variably bias said valve in accordance with engine operate ingconditions and including exhaust gas pressure acting to open said valveand a coiled bimetallic strip thermostat biasing the valve toward itsopen position and having its inner end fixed to said valve member sothat the thermostat is entirely carried thereby, and a relatively fixedbut adjustably movable member to be freely engaged by the other end ofsaid thermostat heater for the induction t which thus actuates the valvein only one direction in accordance with its temperature and theadjusted position of said relatively fixed member, and whereby the valvemay be swung open by the exhaust gas pressure without resistance fromsaid bi-metallic strip.

20. A heat control valve unit to automatically regulate the flow ofheating exhaust gases through a heater in the intake manifolding of aninternal combustion engine having a movable throttle comprising a valveand valve controlling and actuating means responsive to temperature,

' and means'moving with said throttle and connected to act through andto aidv or increase the action of said temperature responsive valvecontrolling means to cause said valve to be moved toward non-heatingposition only at substantially full throttle positions to thereby obtainfull volumetric efiiciency and performance under heavy loads and openthrottle and yet to have maximum heating and economy at all lesserthrottle openings.

21. A heat control for a heater in the induction manifolding of aninternal combustion engine comprising a valve to control the flow ofexhaust gases to said heater and means-to automatically control theoperation of said valve including a temperature responsive means actingto bias said valve only toward its, non-heating positions.

22. A heat control for a heater in the inductionrmanifolding of, aninternal combustion engine comprising an unbalanced-valve to control theflow of exhaust gas to said heater and biased towards its non heatingposition by increased exhaust gas flow and means to automaticallycontrol the operation of said valve inaccordance with engine operatingconditions including a weight always biasing said valve toward itsheating positions and temperature responsive means biasing said valvetoward its non-heating position to thus aid said increased exhaust gasflow.

RAYMOND M ANDERSON.

